176 THE NORTH AMERICAN SLIME-MOULDS 



thallus well developed, black ; columella black, slender, weak, gener- 

 ally dissipated some distance below the apex; capillitium of slender 

 brown or dusky threads anastomosing to form an open network next 

 the columella, but extended outwardly in form of long free slender 

 branchlets, now and then dichotomously forked ; spore-mass blue- 

 black, spores by transmitted light dark brown, globose, spinulose, 

 some of them faintly reticulate, about 9 jx. 



A very remarkable species. Rare in the west, more common, as it 

 appears, in the eastern states. The sporangia occur in tufts about 

 1 or 2 cm. wide, springing generally from crevices in the bark of 

 decaying logs, especially willow and elm, in swampy places. The 

 sporangia are remarkable for their great length. Generally about 

 20-25 mm., specimens occasionally reach 50 mm. 1 The capillitial 

 branches are so remote that the spores are scarcely retained by the 

 capillitium at all. Well described and figured by the author of the 

 species. Forty-third Rep. N. Y. State Museum, p. 24, PI. 3. 



New York, Pennsylvania, Ohio, Iowa. 



5. COMATRICHA IRREGULARIS Rex. 

 1891. Comatricha irregularis Rex, Proc. Phil. Acad., p. 393. 



Sporangia crowded in flocculent tufts, very dark brown or black, 

 semi-erect or drooping, 4-5 mm. in height, irregularly cylindric, 

 variable, stipitate ; stipe black, distinct, often one-half the total height ; 

 hypothallus well developed, brown, shining; columella central, slen- 

 der, flexuous, reaching the apex, where it blends, by branching, with 

 the capillitium ; capillitium loose, open, composed of arcuate threads 

 which radiate from the columella, and are joined together, forming a 

 central, irregular reticulation of large meshes, brown, paler toward 

 the surface, where the free ends are sometimes colorless; spore-mass 

 black, spores by transmitted light brown, minutely warted, 7-8 fi. 



Related, no doubt, to C. longa, but differing in habit, stature, as in 

 texture and structure of the capillitium. In C. longa the inner net is 

 extremely simple, — a row or two of meshes at most, and the radi- 

 ating branches are long and straight; in the species before us the 

 inner network is well developed, and the radiating branches propor- 

 tionately shorter and abundantly branching, with pale or white free 

 tips. 



